Ethylmalonate

Ethylmalonic Acid.—Like acetoacetic ester (see p. 83), diethylmalonate contains the gioup CO.CHj.CO. By the action of sodium or sodium alroholate, the hydrogen atoms of the methylene group are successively replaceable by sodium. The sodium atoms are in turn replaceable by alkyl or acyl groups. Thus, in the present preparation, ethyl malonic ester is obtained by the action of ethyl iodide on the monosodium compound. If this substance be treated with a second molecule of sodium alcoholate and a second molecule of alkyl iodide, a second radical would be in roduced, and a compound formed of the general formula... 

Benzoyl fluoride, 46,3 Benzoy lhydrazine, 46, 85 Benzoyl peroxide, as catalyst for reaction of chloroform with as,as 1,5 cyclooctadiene, 47, 11 reaction with diethyl ethylmalonate, 46, 37... 

C2H,BrMg 925-90-6) see Amfebutamone Dicthylstilbestrol Elhylestrenol Etretinate Fomocaine Indanorex Ketobemidone Mepivacaine Methadone Methallenestril Methohexital Normethadone Olprinone hydrochloride Retinol cthylmalonic acid diethyl ester see under diethyl ethylmalonate ethylmercaptan... 

The mesoionic pyrimido[l,6-tf]pyrimidine 94 was prepared in good yield by reacting 4-ethylaminopyrimidine 90 with bis(2,4,6-trichlorophenyl) 2-ethylmalonate (Equation 8) <2000BMC1917>. 

The resultant ethylmalonate-protected-amine compound is concentrated in vacuo and then purified using silica gel chromatography with a hexane/ethyl acetate (1 1) eluent. 

Add to the Qo solution 100 mg of the purified ethylmalonate-protected-amine compound from step 4 along with 88 mg of I2 and 105 mg of DBU (Aldrich). 

Figure 15.9 The reaction of the amine-blocked derivative of 3-hydroxypropylamine with ethylmalonyl chloride gives an ethylmalonate-protected-amine compound, which can be used in the Bingel reaction to create an amine group on a fullerene surface. Reaction with Cfl in the presence of I2 and DBU gives the cyclopropanation product that can be deprotected with TFA to yield the free amine.

The mixed carbonic anhydride procedure8-7 has been useful in the preparation of amide linkages and thiol esters. Mixed carbonic anhydrides have successfully acylated, under very mild conditions, the carb-anions derived from diethyl ethylmalonate and diethylcadmium.8 The latter gives as a product the corresponding ketone. Mixed anhydrides derived from acetic and acetylsalicylic acids give results similar to those described here.8... 

Ethyl a-nitrobutyrate may be prepared in 75% yield by the reaction of silver nitrite with ethyl a-iodobutyrate.4 It has been prepared in 18% yield by nitration and subsequent decarboxylation of diethyl ethylmalonate.6 The present method offers the advantage of a direct preparation using sodium nitrite. 

Similarly, dimethyl [2-(2-aminophenyl)-l-phenyl]ethylmalonates undergo ring closure to give 3-methoxycarbonyl-4-phenylbenzazepin-2-ones on treatment with sodium methoxide [75],... 

Diethyl Ethylmalonate.—Sodium (4-6 g.) is dissolved, in a small flask fitted with an efficient reflux condenser, in 75 c.c. of absolute alcohol and to the cooled solution 33 g. of diethyl malonate are added (precipitation of diethyl sodio-malonate). To the mixture thus obtained, ethyl bromide (25 g.) or ethyl iodide (35 g.) is added in small portions with shaking and the flask is then heated on the water bath until, after one to two hours, the contents are no longer alkaline. The alcohol is removed by distillation in a vacuum from the water... 

Butyric Acid from Ethylmalonic Acid.—A small distilling flask having a long side tube is fixed in an oblique position with the tube directed upwards. The ethylmalonic acid is placed in the flask, which is then corked and heated in an oil bath at 180° until, after half an hour, evolution of carbon dioxide has ceased. The residue is then distilled from the same flask in the usual way the butyric acid passes over between 162° and 163°. Yield 80-90 per cent of the theoretical. 

The sodium hydride is obtained from Metal Hydrides Inc., Beverly, Massachusetts the diethyl ethylmalonate from Eastman Organic Chemicals. 

Benzophenone, 46, 36 N-(2-Benzothiazolyl)urea, 46, 72 Benzoyl chloride, reaction with hydrogen fluoride, 46, 4 Benzoyl fluoride, 46, 3 Benzoylhydrazine, 46, 8S Benzoyl peroxide, reaction with diethyl ethylmalonate, 45, 37 2-Benzyl-2-carbomethoxycyclopenta-none, 45, 7... 

To a 1-1., three-necked, round-bottomed flask is added 7.2 g. (0.15 mole) of a 50% dispersion of sodium hydride in mineral oil (Note 1). The sodium hydride is washed several times by decantation with dry ether and is then covered with 300 ml. of dry benzene (Note 2). The flask is equipped with dropping funnel, stirrer, and reflux condenser. Diethyl ethylmalonate (28.2 g., 0.15 mole) (Note 1) is added dropwise over a 5-minute period, and the reaction mixture is stirred for 2 hours until a clear solution forms. The solution is cooled in an ice bath, and 24.2 g. (0.1 mole) of benzoyl peroxide (Note 3) in 300 ml. of dry benzene is added dropwise over a 1-hour period with continuous stirring After another 30 minutes, a peroxide test (Note 4) is made to ensure that all the peroxide has reacted. 

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